Black Box 32144, Руководство пользователя

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CHAPTER 3: Options: Customizing the Modem Setup
Dialup Applications
For dial line use, the carrier detect
level can be set for –51, –41 or –34
dBm. The default setting is –51
dBm.
Transmit Level
All modes
This option controls the modem’s
transmission level. To make a
selection, first select either
LEASED or DIAL from the
TRANSMIT LEVEL screen.
Leased Line Applications
For leased lines, the transmission
level can be set between 0 and –15
dBm, in 1-dBm steps. The standard
setting is 0 dBm. (Use pushbuttons
1 and 3 to select the desired
transmission level.)
Dialup Applications
The transmission level for dial lines
can be set as either programmable,
if you are using RJ-45S connectors,
or permissive, fixed at –10 dBm
+/–1 dBm, which is the most
common setting.
Signal Quality
All modes
This option sets the threshold for
the ER (error) indication during
normal operation. You can choose
either 10^3, one error in 1000 bits,
or 10^5, one error in 100,000 bits.
The settings of the Signal Quality
and Carrier Detect Level options
determine the threshold values the
modem uses as criteria for entering
Leased Line Auto-Recovery mode.
Compromise Equalizers
Hayes, V.25 bis, Dumb, Leased-line
modes (except V.33)
NOTE
The compromise equalizers
only affect V.32 operation
(4800 bps to 14.4 Kbps,
asynchronous/synchronous,
full duplex).
For most applications, the
automatic adaptive equalizer
setting will provide all the equaliza-
tion necessary to compensate for
line impairments, meaning that
equalizer adjustments generally will
not be necessary. However, in the
event that equalizer adjustment is
needed, any of four types of
compromise equalization can be
selected: Type I (T-I on the LCD),
Type II (T-II), Type III (T-III) and
Type IV (T-IV). The equalizer can
also be turned OFF.